3.5

## National STEM Learning Centre

Skip to 0 minutes and 13 secondsHow are we gonna push it along? You said we think we got a boat. As soon as we got wind resistance, we're gonna use that to push it along. What else do we need? You said there's something else. We need a sail. A sail. Paper, we can cut it out of paper. And then when we start blowing this, will be time. Okay, time for what? [INAUDIBLE] How are we going to measure how strong it is? Time for what? Let's see how far it takes to get from one side to the other Maybe. [CROSSTALK] Now I've put a little title at the start of that sheet. What's the title at the start of that sheet for me?

Skip to 0 minutes and 57 secondsJosh, give that title a little read, just. Investigating what affects wind resistance. What? Affects. Good, we're investigating what affects wind resistance. And most of you are absolutely right, we're going to do something with the boat, we're going to do something with sail, and we're going to time it with a stopwatch, I'm not trying to give too much away here. What affects this force of wind resistance okay? That's what we're trying to do today. Now we're gonna plan this first off. Before we can do anything we need to get a good plan in place. So what are all the possible things that we could or could be changed in your minds with this experiment?

Skip to 1 minute and 31 secondsYou know that we've got a guttering, we know that we're gonna get a boat from one end to another. You know that we've got to do something with the sail. What is one thing you think we could possibly change as we start testing. Write it on your post it note and then stick it in one of those yellow boxes and we'll have a listen to some of the ideas that we get down. Is there anything that we could change when we go downstairs later on? How much water is in the pipe? Okay, nice. Put that on there. Spot on. We could like cut, like the paper? Okay. So like the wind thing, and then pop it on there?

Skip to 2 minutes and 7 secondsOkay, so what we changing then? Shapes of the sail. Shapes of the sail? Yeah. So your talking like triangles and circles. No, no keep it on that. Cuz you could change that. We could. That is a variable we could change. I'm not saying we are going to, but we could change it, couldn't we? What did you mean then? How big the circle is, okay. If it's smaller it may not move as well. [CROSSTALK] If it's bigger more wind can hit it. Yeah, so it can move faster, because there's more- Are you confident, 100% sure of that one? Yeah. Maybe. I don't know. Because if the sail is smaller, then it will go slower.

Skip to 2 minutes and 31 secondsAnd if it's bigger then it will get-. [CROSSTALK] Write it all the way down to the spot box there, kind of a prediction. Yeah. Who wrote less things of all the things that could change? Let's have a listen then. Here. The length of the gutter? Nice. Yeah, we could change the length of the gutter. That could change easily. Length of the gutter. What else could we change? That's a good option that one, Karen. Brilliant, something else. Something else, next. Yeah, you could change the shape of the sail. The shape of the sail. How much water is in the pipe. How much water is in the pipe. If there's no water in the pipe, It would be.

Skip to 3 minutes and 17 secondsImagine how strong the wind is showing. Any other variables, Alan? The difference where we put the fan, say if you put it far away. Nice. The distance of the fan. That's a very good one. What happens if it's gonna go far away, then? Talk at your tables. What's gonna happen if the fan is further away or if it's closer?. [CROSSTALK] And yeah when it all spins the, like when it's spread out. [CROSSTALK] If it's fairly close. It's coming straight from the facts. If it's further away, it has to travel. Three two one, John. You could change the size of the sail. Good, change the size of the sail, so the size of the sail.

Skip to 3 minutes and 55 secondsWhy is that different to the shape of the sail? What's different about that? Dan?. Because if the sail is bigger then the wind of the fan or perhaps the sails are [INAUDIBLE] What's different about the size and shape? What's different about those two words? I think some people when they put down shape might have thought size, but it's actually a very different meaning. Joe? Because the size. Because the size, it could be small or large. But you could have a circle that's big or a circle that's small, that's the sail. Good, yeah good. Circles, squares, and triangles, they're all different shapes. But size-wise we give you the same shape but change the size of it. Charlie?

Skip to 4 minutes and 41 secondsAnd the direction of the fan. Yeah the direction of the fan. That's a good one. I hadn't thought of that one. Direction, brilliant. Right, we'll come back to those in a minute. They're all of our variables. Now we need to choose how many variables are we allowed in any test, really? We're trying to keep it simple, we're trying to keep it effective. How many variables do we want? One. Josh? Say again. One. Good yeah. We just want one variable, one variable. Cuz otherwise we're trying to juggle ourselves over and then look, we need to change that, then we need to change that, and get back to the other one, this one. One variable that we can change.

Skip to 5 minutes and 14 secondsOn your tables now, using the blue post it notes, can you think to yourself what is one thing we could measure that says, that will help us test the effects of wind resistance? The sail? You could measure the length of the sail. Is that gonna answer our question? What's our question again? That we are investigating what affects wind resistance? Is ithe length of the sail gonna help us? But you know what? We could measure that. So get it down, let's get it on our board. Cuz it's an option. You're smart that we could measure that. Let's keep it. [INAUDIBLE] How far it goes, how far it goes, how far away the front is.

Skip to 5 minutes and 48 secondsOkay, what have you got on your tables that could help you? What else could you measure using some of the equipment on your tables? What time? Say that again. What time? What do you mean, what time what? What time it is? No, what time it takes to get across. Right, is that something we could measure? Yeah. Well let's get on that because these are all the possibilities. We now need to choose one of these variables that we are definitely going to change, only one. And we're going to choose one of these variables that we're definitely going to measure, okay? Once you've chosen them, we can move them down here and we're going to create a question.

Skip to 6 minutes and 22 secondsWhat is the variable that we're going to change? What is the variable we are going to measure? If you've got them on your table, if you want to add any, pull them up and stick them down on the bottom there. We could change the size of the boat. The shape of the sail. Yeah. The shape of the sail. You could change that size or the shape of the sail. That's two things. It has to be one, shape or sail? Shape. No, shape. Shape. Shape. Shape, yeah. It's supposed to be more like that... [INAUDIBLE] [CROSSTALK] That's two things. That's two things.. [CROSSTALK] Size is one thing, shape is another. So you can have a small circle and a bigger circle.

Skip to 7 minutes and 6 secondsYou can change the size, and you can also change the shape. I got one. How long it takes to get to the other side. I got one. How long it takes for you to get to the other side. Yeah. We decided over there, we'll change the size and shape. How many things is that, that you're changing? Two. Changing two. Can only change one. So then Joe said all right, we'll change the shape. I said that's fine, but then you have to keep the size the same. Joe, what were we just talking about? What term? The amount, the size of the surface area. Good, the surface area. You're gonna only change the shape.

Skip to 7 minutes and 23 secondsYou have to keep the size exactly the same. So if I drew a circle here, let's say I did some very complicated maths to find that comes exactly 26 cm square. Then when I draw a triangle, I've gotta make sure that that area, again that's covered, is exactly 26 cm square. And if I draw a rectangle, I've got to make sure it's exactly? 26 centimeters squared. If I draw a hexagon is gonna be exactly? 26 centimeters squared. If I draw a pentagon is gonna be exactly, Daisy? 26 centimeters squared. 26 centimeters squared. Because the size is gotta stay the same.

Skip to 7 minutes and 59 secondsSo if you wanna change the shape fine by me, but I hope you know how to measure the surface area of a circle. Carry on. All right, Alan, food for thought. How about the size? The shape of the sail. [INAUDIBLE] The size of the sail. [CROSSTALK] Okay, so we will change the size of the sail. We can do medium. Yeah, you can do medium or massive. [CROSSTALK] Okay, so what are we gonna do to measure it? [CROSSTALK] Massive, mini, tiny, medium. Yeah, I think size. Yeah that makes sense. Yeah. If we change or pick this service, what will happen to how long it takes? Does that make sense? It could take longer shots.

Skip to 8 minutes and 34 secondsNow if you move them down, you should be able to find me now. Move them one more step down to that next box and we should have generated a question. And the question should make sense. Might need to reword it slightly. If we change the size of the sail, [INAUDIBLE] of the sail, what will happen to how long the boat takes to get to the side? Or the time it takes the boat to get to the other side? There are two more things we need to do as good scientists, I'm afraid, until we can build it. First one, the pink boxes at the bottom. Our predictions are? Our predictions. What is a prediction?

Skip to 9 minutes and 13 secondsTowards the person next to you, what is a prediction? A really good guess, like it's a really good.. [CROSSTALK] Max, say that again. You give me. Well, it's a good prediction.. [CROSSTALK] What you think's gonna happen. Yeah, what you think's gonna happen. It will get bigger, it will get.. [CROSSTALK] Right, Josh, what did we predict? The bigger surface is. Nice. Good language. More wind's going to catch it and make it further. But say it's- Well, we're already measuring how long it's gonna take, not measuring how far it's gonna go. So reword that a little bit. So you predict that the more surface area, The quicker it'll take. Yes. The less time. Cuz it has more to hit.

Skip to 10 minutes and 18 secondsGo on, say that. Becasue it has more to hit. But if it's a smaller object It has less to hit so, yeah. Yeah. And when we say less to hit, what was that technical vocab I was trying to get people to use before? Tests. Surface. Surface. Area. Good. The smaller the surface area, you're right. In one sense, as Harvey said, there's less of an area for the wind to be caught by. So we're hoping the larger it is, there's more chance it's gonna be caught. And you predict It's gonna take less time. Okay. Because the wind will just move straight past it. Yeah. But it's big, then more wind can hit. Yeah. Make sure they're all.

Skip to 10 minutes and 34 secondsMake sure they're all five centimeters. Five centimeters from the- Start it from zero. Yeah, I did start at zero. It's big. It isn't that big. How can you find that sign? Yeah. And then it's 78 centimeters squared. [CROSSTALK] All right. 50 cenitmeters squared. Told you. [CROSSTALK] How are we attaching these to the boat? That's the last thing we need to do. Poke through with your pencil. Then you've gotta be careful you don't rip it. Bingo.

# Whole class investigation: planning

These two videos follow a whole class investigation. The children are Year 5 (age 9 and 10) and they are learning about forces. The lesson follows the entire investigation process from initial question through to conclusion.

The children begin by talking about air resistance and investigating the best sails for a boat.

In the video you will see the children using a planner to help them organise their ideas and strategically work through the investigation.